| 摘要 |
The premolding of predetermined deflection in the top wall (13) of plastic closures (10) for pressure or vacuum applications is described. The premolded deflection is to compensate for pressure forces, or atmospheric pressure in the case of vacuum, within the sealed container so that the closure, after sealing, will be essentially flat in appearance and better able to maintain a pressure seal from both a short term as well as long term sealing application to a jar or bottle. |
